1. Field of the Invention
The invention relates to an electrical switch, in particular an electrical microswitch, comprising at least one electrical contact.
2. The Prior Art
Electrical switches are used in electrical power circuits for the switching on and off of electrical loads. Often these kinds of power circuits are miniaturized, so that they can also be integrated into complex technical devices. In particular, miniaturized switches are used in vehicle construction, which switches control the various functions in a vehicle. Microswitches of this kind are found in e.g. door locks, bonnets, tailgates and in the interior of the vehicle.
Electrical switches, in particular microswitches, have at least one electrical contact that participates directly in the conduction of the electrical current. For this purpose, the contact consists of an electrically conducting material; it can be applied onto an opposing contact or to other electrically conducting sections in order to enable a flow of current.
In the prior art, contacts are used that are manufactured from solid material. In a further work operation, the solid material is attached to the contact support. A welding on of wire sections as a contact, or a riveting of contacts onto the support material is usual. Silver (and its alloys) or coating materials with silver and copper components find application as the solid material. Low hardness is a common factor for these materials.
The contacts of solid material have an increased mass, which causes problems because of the high dynamics of the switching process. A problem of a high mass is, e.g., that when it is applied onto an opposing contact, vibrations can occur that cause a temporary lift-off of the contact from the opposing contact. This is particularly the case if the contact is introduced to the opposing contact in an accelerated manner. With an impact of the contact of this kind, impulsive events can occur that cause multiple liftoff of the contact, as a result of which the current flow that is actually-desired is interrupted.